1. Field of the Invention
The invention is specifically designed for use in sailboat racing applications where true wind speed and direction are desired for purposes of planning proper sail utilization on the next tack. However, the device has applications in any wind powered vehicle and may be useful for navigation in airplanes.
2. Description of the Prior Art
The prior art teaches various devices capable of forming an infinite number of triangles. However, enclosing such a device in a weatherproof box and provided external controls for varying the triangle is not taught. Many of the devices taught also must be used on flat stable surfaces so that pitch and roll of a sailing vessel in heavy seas would interfere with use of the device or make it more difficult.
For example, in Banner, U.S. Pat. No. 3,863,347, a navigation device capable of forming an infinite number of triangles is taught but no weatherproof enclosure with external controls is specified or claimed. Also, the device has 4 arms instead of 3 and is used for a different purpose, i.e., to determine the effect of wind and current on the course of a moving vessel. This is an entirely different problem than solved by the present invention.
In Klauberg, U.S. Pat. No. 3,486,232, a device is taught to form an infinite number of triangles and which could be used for the same purpose as the present invention. The device can measure the length of each side of the triangle and the angle between each pair of sides. However, the device would have to be used on a flat stable surface. The construction taught leaves the sides free at all times to slide to new unwanted settings. Further, the scales used on the Klauberg device are not suitable for solution of the wind vector problem. Only two sides in the present invention move on trackways, not all three. Finally, there are gradations on only one moving arm in the present invention and another side is measured by means of a scale on a gear engaging that side and enabling its adjustment.
In Gabriel, U.S. Pat. No. 3,083,901, a device is taught that can solve right and oblique triangles. However, the device does not teach a weatherproofenclosure nor external knobs for controlling the setting of various sides.